Saw-operating mechanism.



No. 720,944. y Y PATENTED PEB. 17, 1903.. J. MEIKLEJOHN.

SAW OPERATING MEGHANISM.

APPLIGATION FILED MAY 17. 1902.

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PATENTBD FEB. 1'7, 1963.

J. MEIKLEJOHN.. SAW OPERATING MEGHANISM.

APPL'IUATION FILED MAY 171 1902.

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To all whom, it 11i/ty concern:

Be it known that l, JAMES MEIKLEJOHN, a citizen of the United States, and a resident of Sedro Woolley, in the county of Skagit and State of Washington, have invented a new and Improved Saw()perating Mechanism, of which the following is a full, clear, and exact description.

This invention relates to improvement-s in mechanism for operating crosscut-saws, the object being to provide in connection with a saw steam or other pressure actuated pistons that operate to draw the saw through the Work in both directions instead of with a pushing motion, which might cause a buckling or breaking of the saw.

I will describe a saw-operating mechanism embodying my invention and then point out the novel features in the appended claims.

Reference is to be had to the accompanying drawings, forming a part otthis specification, in which similar characters of reference indicate corresponding parts in all the gures.

Figure 1 is a front elevation of a saw-operating mechanism embodying my invention.

Fig. 2 is a partial section andpartial eleva-M tion of a part of the actuating mechanism. Fig. 3 is a section on the line :r a: of Fig. 2. Fig. 4 is a section on the line y y ofY Fig. 2, and Fig. 5 is a section through one of the valves employed.

The frame of the machine comprises the.

outer uprights 1, the inner uprights 2, and the head or top rail 3. Movable vertically along the frame at opposite sidesof the uprights 2 are the carriers 4 5, each consisting of metal plates having outwardly-extended anges at the top and bottom. The carrier 4 is moved by screw-rods 6 7, which engage in tapped openings in lugs 8, extended rearward from the carrier. These screw-rods have bearings 9 at their lower ends and bearings 10 at their upper ends. Attached to the upper ends of the screw-rods 6 and 7, respectively, are bevel gear-pinions 11 12, which engage with bevel-pinions 13 14 on a drivingshaft 15, operated by any suitable source of power. The carrier 5 is also operated by screws 16 17, having 'bevel-pinions 1S 19, engaging with bevel-pinions 2O 2l on the shaft 15. These carriers support the saw and the JAMES MEIKLEJOHN, 0F SEDRO WOOLLEY, VASHINGTON.

SAW-OPERATING MECHANISM.

SPECIFICATION forming' part of Letters Patent No. 720,944, dated February 1'7, 1903.

Application filed May 17, '1902. Serial No. 107,794. (No'model.)

devices for operating the same, and to cause the easy movement of the carriers, or, in other words, to reduce as much as possible the weight sustained by the screws, cables 2 2 extend from thecarriers over pulleys 23 on the top rail 3, and the free ends ot' these cables are provided with weights 24.

Supported on the carrier 4 is a cylinder 25, in which a piston 26 operates, the stem 27 of the piston connecting with a cross-head 28, movable on guides 29 on the'tlanges of the carrier. On the carrier 5 is a cylinder 30, in which a piston 26a operates, the stern 21 of the piston connecting with a cross-head 32, movable on the guides 33 on the anges of the'carrier. The cross-heads 28 and 32 are connected to the ends of the saw 34 by castings 35. Steam-pipes 36 lead into the cylinders at the inner ends, and arranged in each pipe is a valve-casing 37, from which an exhaust-pi pe 3S leads.l Operating in each valvecasing is a plug-valve 39, having a main port 40 and an exhaust-port 41. On the stem of each valve is a linger 42, designed to be engaged by either one of the tappets 43 44 on the ends of a shifting rod 45, attached to the cross-head.

In operation the log of wood is to be placed underneath the saw on the support or slide 46 between the upright-s 2. The motive agent will be conducted tothe pipes 36 by a iexible pipe to permit of the upward and downward movement of the carriers, and assuming the steam to be entering against the piston in the cylinder 30 the valve 39 for the cylinder 30 will be in the position indicated in Fig. 5, but the valve for the other cylinder will be turned one-quarter of a revolution to bring the ports 40 and 41 into position to exhaust through the pipe 38 of the cylinder 25. Upon 'reaching the end of the motion in this direction the tappet 43, carried by the cross-head 32, will engage with the finger 42 turning the valve of the cylinder 30 to` exhaust position, and the tappet 44, carried by the cross-head 2S, will move the valvefor the cylinder 2,5 into position to admit the motive agent. Then the reverse action will take place. During the reciprocating movements of the saw it is obvious that the carriers will be moved downward by means of the screw-rods, as before ".UNITED STATES PATENT OFFICE.

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described. Upon sawing through the timber the direction of rotation of the screw-rods is to be reversed to raise the carriers and saw.

Having thus described my invention, I claim as new and desire to secure by Letters Patentl. In a saw-operating mechanism, a frame, opposite carriers mounted to move vertically along said frame, each carrier consisting of a plate having outwardly-extended flanges at its upper and lower edges, guides on said iianges, a cylinder mounted on each carrier, cross-heads operated by pistons in the cylinders and movable along said guides, a saw having connection with the cross-heads, and means for operating the carriers.

2. In a saw-operating mechanism, a frame, opposite carriers mounted t0 move vertically along the said frame, each carrier consisting of a plate having outwardly-extended ianges at its upper and lower edges, guides on said fianges, a cylinder mounted on each carrier, cross-heads operated by pistons in the cylinders and movable along said guides, a saw having connection with the cross-heads, means for operating the carriers, and means for automatically controlling the supply of motive agent for: the cylinders.

3. In a saw-operating mechanism, a frame, opposite carriers mounted to move vertically along said frame, each carrier consisting of a metal plate having outwardly-extended anges at its upper and lower edges, guides on said flanges, a cylinder carried by each carrier, cross-heads having connections with the pistons in the cylinders, the said crossheads being movable along said guides, a saw having connection with the cross-heads, lugs extended rearward from the carriers and having threaded openings, screw-rods engaging with the threads of said lugs, means for simultaneously operating the screw-rods, and means for automatically controlling the inlet and exhaust of motive agent for the cylinders, substantially as specified.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

JAMES MEIKLEJOHN.

Witnesses:

GORDON HooPEs, M. PARNELL. 

